Friday AM I was unable to start my Mooney: 1965 M20E; Lycoming IO360A1A;
Slick Magnetos; Starter Vibrator; Bendix ignition/starter switch.

The engine would turn, and fuel would flow (actually dripped out onto the
ground after a while), but no sign of "fire".

Subsequent troubleshooting revealed that a wire from the condensor on the
starter magneto (I think it's the left) had its insulation worn through by
rubbing on a portion of the case internally and may have been shorting out.

During this troubleshooting process, it became apparent that we were not
hearing the noise of the starter vibrator (although I cannot be certain of
that being the case prior to the arrival of my IA).

After rerouting that wire so that it could not possible short out to the
case, the engine started normally, both on that day and a few days later.

My question: Is it possible for this possibly shorted condensor wire to
inhibit the starter vibrator from "vibrating"? If so how?

The POH only shows the connection to the ignition switch, and nothing about
the high voltage side of this unit.

My fear is that I may also be dealing with either an intermittent starter
vibrator, or an intermittently dysfunctional ignition switch.


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)